Vitamin D must go through several processes in the body before it can be used. It begins when the liver converts vitamin D into a chemical called 25-hydroxyvitamin D. Therefore, the 25-hydroxyvitamin D test is the best way to monitor vitamin D levels in the body. It is also an important indicator of osteoporosis and rickets.

Vitamin D plays an extremely important role in the body, however, deficiency of this vitamin is very common. Therefore, measuring blood vitamin D in a general health check-up helps to accurately assess the amount of vitamin D in the body, thereby helping to detect early vitamin D deficiency for timely supplementation.